This invention relates to a range of products and the art of preparing those products for inhibiting the effects of or reducing the risk of contracting a disease which, in many cases, has a significant impact on the economics of dairy farming.
The disease is parturient hypocalcemia or milk fever. This is a condition, to quote Ensminger, (xe2x80x9cDairy Cattle Science,xe2x80x9d M. E. Ensminger, Third edition (1993), Interstate Publishers, p. 287): xe2x80x9cAt or soon after calving (generally within 48 to 72 hours), a sharp decrease in blood calcium (hypocalcemia) occurs in some cows, resulting in a loss of appetite, subnormal temperature, and an unsteady gait. This is followed by nervousness, and, finally, collapse or complete loss of consciousness.xe2x80x9d The triggering mechanism for the hypocalcemia, i.e., drop in blood calcium is the onset of lactation which causes an intensive mobilization of calcium. Unless treated, the disease can cause death and, therefore, the loss of the animal as a future milk producer.
The losses to the dairy farm economic sector can be significant. The total number of milk cows in the United States is in the order of 10 million. (See, for example, Ensminger, op. cit., p. 9), of which perhaps 60% are pari-parturient and at risk for the disease. From a total milk production point of view alone, the 10 million milk cows represent about 1,500 billion pounds of milk in a given year. It is estimated that approximately 8% of all lactating cows are affected by clinical milk fever. It has also been estimated (Horst, et al., 1997) that the disease can reduce the productive life of a dairy cow by 3.5 years. Based upon its studies (C. Guard, Cornell Veterinary College, as reported in Hoard""s Dairyman, January 1996) Cornell University further estimated that the average cost per milk fever case was $334. This value represented the direct cost of treating the clinical cases and the estimated production losses of milk. Multiplying the number of potential cases by the $334 per case yields an estimated total loss to the U.S. dairy industry of $160 million per year. Another factor affecting economic losses is that milk cows contracting milk fever are also more susceptible to a host of secondary problems, which include ketosis, mastitis, dystocia, retained placenta, displaced abomassum and uterine prolapse (Horst et al., 1997). Each of these secondary problems has as the least consequence a reduction or further reduction of milk production.
Since milk fever has such a major impact on the economy of dairy farming in the United States and elsewhere in the world, a considerable amount of research has been directed towards its prevention and cure.
Perhaps the most significant early research was reported by a group of Norwegian researchers (Ender, F. and I. W. Dishington, 1967, xe2x80x9cComparative Studies on Calcium Balance Levels in Parturient Cows Fed Diets Inducing and Preventing Milk Fever.xe2x80x9d 557Am XVIIIth World Veterinary, Congress, Paris, France) who demonstrated that the effect of various cations in dietary rations of a dairy cow in terms of promoting milk fever incidence could be prevented by adding anions in the form of hydrochloric and sulfuric acid. However, they realized that with the other feed ingredients at their disposal at the time, using these highly corrosive acids in their un-reacted forms would pose a serious hazard to both dairy cattle and dairy farm personnel. Thus, the conclusion of these researchers was that instead of these pure acids, related anionic salts, such as calcium chloride, ammonium sulfate, aluminum sulfate and magnesium sulfate, should be considered.
Based upon these findings, other researchers (most prominently Goff and Horst) then started evaluating these anionic salts. They found that while these salts are relatively easy to handle, there are a) problems of palatability and b) the intrinsic problem that while salts contain anions, they also contain cations which, depending upon their rate of absorption, will negate some of the positive effects of the anions.
The same paper (J. R. Goff and R. L. Horst, xe2x80x9cUsing Hydrochloric Acid as a Source of Anions for Prevention of Milk Feverxe2x80x9d, USDA Prepublication (1997)) compares hydrochloric acid with the anionic salt calcium chloride and shows the advantage of the former over the latter. The authors also discuss in some detail comparative feeding studies involving dairy cow diets with or without hydrochloric acid and show the ability of a diet with hydrochloric acid to control milk fever. In a subsequent paper, xe2x80x9cUse of Hydrochloric Acid as a Source of Anions for Prevention of Milk Feverxe2x80x9d, J. Dairy Science, November 1998, p. 2874-2880), the same authors, Goff and Horst, provide further evidence for their earlier conclusions.
While this paper is substantive in its proof that, to quote the authors, xe2x80x9chydrochloric acid is an inexpensive, xe2x80x98palatablexe2x80x99 alternative to anionic salts as a means of controlling milk fever,xe2x80x9d the palatability is only improved as compared to those of the anionic salts. Hydrochloric acid used with the formulations studied is still difficult to administer as the dairy cow does not want to consume it in the quantities required.
Because of the problems mentioned, with respect to acids, past research was focused on preparing formulations using anionic salts and not those using hydrochloric or sulfuric acids.
For example, Rebhan (Herbert J. Rebhan, U.S. Pat. No. 4,931,290, xe2x80x9cMilk Fever Prophylactic Treatment and Composition) describes a method for xe2x80x9creducing the propensity of a dairy cow to develop severe milk fever upon calving comprising of administering thereto a composition (consisting) of a water soluble calcium compound and a complexing agent for serum phosphorus.xe2x80x9d That patent discusses the use of (anionic) calcium salts of hydrochloric and organic acids supplemented with a complexing agent to form water-insoluble compounds of serum phosphorus. The combinations of these compounds are presented as having a favorable effect on the blood anion-cation balance and, thereby reducing the incidence or curing milk fever.
A further example, Kjems (Gunnar Kjems, U.S. Pat. No. 5,393,535, xe2x80x9cOrally Administrable Calcium Supplement for Cattlexe2x80x9d), describes a composition wherein a calcium ion, i.e., an anionic salt is dissolved in water but the water phase is dispersed into a continuous oil phase, forming an emulsion by means of a nonionic emulsifier. This method of preparation is presented as compatible with oral administration of the composition and as palatable to the dairy cow because of the oily phase.
In another example, Goff and Horst (Jesse P. Goff and Ronald L. Horst, U.S. Pat. No. 5,560,920, xe2x80x9cCalcium Formulations for Prevention of Parturient Hypocalcemiaxe2x80x9d) present that calcium propionate, i.e., an anionic organic salt may be mixed with propylene glycol and either citric or phosphoric acid to form a nonhardening paste or with sodium chloride to form a liquid drench. It is stated that these formulations are particularly effective in treating the hypocalcemia associated with the onset of lactation in dairy cows. The inventors argue that calcium-containing gels can be made with water-insoluble carriers (as discussed by Kjems) such as oils or with water-soluble carriers such as propylene glycol. They state that the former tends to decrease the availability of calcium for absorption, but that the gels formed with propylene glycol are more readily soluble in water and thereby increase the availability of calcium.
In still another example, Abele (Ulf Abele, U.S. Pat. No. 5,631,289, xe2x80x9cUse of Calcium Formate in Orally Administrable Compositionsxe2x80x9d), discusses the advantages of an anionic salt of formic acid, i.e., calcium formate in the prophylaxis and metaphylaxis of calcium deficiency in dairy cows. It is stated that the resorption of calcium formate is comparable to that of calcium chloride, but that the former is not corrosive or irritating to the membranes of the digestive tract and thus it is both more palatable and is also less dangerous to the animal if per chance the formulation is inhaled in the respiratory tract, as compared to calcium chloride formulations. Even so, the patent recommends that the calcium formate be bound in a gel or paste to further improve palatability and further lessen the chance of ingestion into the respiratory tract.
The background material presented above summarizes current knowledge. That knowledge may also be stated as follows:
To reduce the incidence of or cure milk fever, it is important that the dry cow has the proper anion-cation balance in its body fluids. There is an equation, referred to as the xe2x80x9cdietary cation-anion difference equation,xe2x80x9d which describes the effect diet cations and anions will have on blood and urine pH of the dry cow. This equation shows dietary effects of the individual ions, such as the cation sodium, potassium, calcium and magnesium and the anions, chlorine, sulfur and phosphorus. Based upon other dietary considerations, phosphorus, magnesium and sulfur (in its sulfate form) and calcium have certain intake limitations. Sodium and potassium should be kept as low as possible in keeping with the management of the forages available. Dietary chlorine should be optimally kept at 0.8 percent by weight. Monitoring urine pH is the best means to determine if more or less anions are needed. A typical target is a pH of 6.2 to 6.7 in Holstein cows.
The products of the present invention are highly palatable and, therefore readily consumed by the dry cow. They are highly effective in controlling urine pH and maintaining it within the desirable range and thus inhibiting the effects or reducing the risk of contracting the disease.
The invention presented here relates to a range of products for inhibiting the effects or reducing the risk of contracting parturient hypocalcemia or milk fever in dairy cows and to a method for preparing same. These products are prepared using a soybean meal extracted from soybeans which were treated according to a method described in detail in U.S. Pat. No. 5,225,230, incorporated herein by reference.
In accordance with the present invention, soybean meal prepared according the method of U.S. Pat. No. 5,224,230 is mixed with hydrochloric acid and other ingredients to enhance or balance the feed value of the mix to form a product that in relatively small daily dosages prevents and treats milk fever in dairy cows as it is readily consumed by the animal because of its high degree of palatability.
Soybeans are comminuted to a particle size range suitable for the physical and chemical reactions of the subsequent steps.
Next, the comminuted soybean particles are reacted at a high temperature, in the range of about 235 to 350 degrees Fahrenheit, for the purpose of converting the soybean solids contained therein into a high bypass protein product. The high temperature heated soybean particles are subsequently fed to a screw press for the mechanical removal of soybean oil. The solid product discharging from the press is generally referred to as soybean press cake. This product is subsequently ground to produce a high bypass protein meal.
To prepare a formulation, the high bypass protein meal prepared from soybeans is mixed in a blender vessel with a quantity of hydrochloric acid of an appropriate Baume strength for a period of time to allow the hydrochloric acid to be completely absorbed and homogeneously blended.
One significant formulation consists of one part by weight of Baumxc3xa9 (36% acid by weight) hydrochloric acid added to three parts by weight of the high bypass soybean meal. This formulation could contain up to 25% moisture by weight. Further increasing the concentration of hydrochloric acid, i.e., increasing the Baumxc3xa9 strength over 22, results in a product with excessive hydrochloric acid odor.
Another significant formulation consists of one part by weight of 20 Baumxc3xa9 (31.5% by weight) hydrochloric acid added to 3 parts by weight of high bypass soybean meal. Formulating this product with a much lower Baumxc3xa9, i.e., a lower concentration would result in a product that is too wet and therefore may cause materials handling problems. The lowest Baumxc3xa9 is considered 18 (approximately 27.5% by weight). One part of this acid added to 3 parts of high bypass soybean meal would contain up to 28.6% of moisture by weight.
To prepare a range of additional formulations, a quantity of the high bypass protein meal prepared from soybean is mixed in a blender vessel with a quantity of hydrochloric acid of an appropriate Baume strength and one or more further ingredients for the purpose of further increasing palatability, controlling the strong hydrochloric acid odor, dust control and prevention of particulate matter entering the animal""s respiratory tract and improving the nutritive balance of the mix in terms of energy, nitrogen, fiber and mineral content.
One ingredient found useful in controlling hydrochloric acid odor is calcium carbonate, which best should be used in its commercially available form such as feed grade limestone or ground oyster shells. One part of either feed grade limestone or ground oyster shells may be added to each four to six parts of hydrochloric acid in the mix.
A benefit of the present invention is that the high temperature step in preparing the soybean material for subsequent mechanical removal of oil, i.e., screw pressing, results in solids which, once ground to form a meal, are highly palatable in their own right and show enhanced palatability once blended with hydrochloric acid.
Yet another benefit of the present invention is that the milk fever inhibiting properties of the specially high temperature treated soybean meal with hydrochloric acid can be further enhanced by blending in ingredients which add further desirable medical and nutritive properties.
Still other benefits and advantages of the present invention will become apparent to those skilled in the art upon reading and understanding of the following detailed description.